Corner die



J. A. McG

CORNER DIE Filed Oct. 8, 1925 3 Sheets-Sheet 1 Id. n1

Nov. 4, 1930. J. A. MCG EGOR 1,780,432

CORNER DIE Filed Oct. 8, 192a 5Sheets-Sheet 5 attozmq Patented Nov. 4, 1930 UNITED STATES JAMES A. HUGE-E603, OFCLE'VELLND, OHIO GOBNEB DIE Application filed October 8, 1926. Serial 10. 140,868.

This invention relates to flanged sheet metal articles and particularly to the manu-" pending peripheral flange in one pressing operation," and when desired, the sheet metal has been provided with a beaded edge simul- Eaneously with the forming of the peripheral ange.

The above method of manufacture has been very satisfactory where the number of articles of a particular size to be formed has been sufficient to warrant the construction of a special. die. On the other hand, where it is desired to form, for example, a relatively .25 small. number of substantially rectangular table tops of an odd size the cost of providing a special die for such articles is prohibitive. An object of my invention is to provide apparatus for forming a depending corner flange in sheet metal.

Another object of the invention is to provide a die mechanism whereby a smooth depending corner flange may be formed in sheet metal.

A further-object of this invention is to provide a punch and die and associated mechanism whereby a smooth depending corner flange and a beaded edge may be formed in sheet metal by a single operation.

Other objects of the invention Wlll be ap parent to those skilled in the art from the description of .it hereinafter 'given.

The present invention may be said to con-v template improved apparatus whereb. a depending corner flange may be readily ormed in sheet metal. Thus, one embodiment of my invention comprises a punch and die with associated mechanism, whereby sheet metal may be firmly held in position during theforming operation, and arelatively smooth depending corner flange produced therein. A beaded edge adjacent the top portion of the flange may also be formed in the sheet metal simultaneously with the "formation of the corner flange.

By means of my invention, therefore, flanged corners may be suitably disposed on sheet metal to form articles of any size. The flanged corners may be arranged furthermore to form articles of substantially rectangular or other poly onal shape. It will be understood that. mec anism-o my invention may be arranged to form corners having sides of any desired angularit Thus, corners of acute, rectangular, or o tuse an; gularitj may be readily formed. i

. After sheet metal has been provided with corner flanges at the desired positions, the portions intermediate said corners may-'be flanged in a subsequent operation to, formv a. peripheral flange. It will thus be seen that by suitablydisposing corner flanges on sheet metal according to my invention, table tops and the like maybe readily formed: of any desired dimensions without requiring special die meehanism'for each size of article to be formed. I

In the drawings, Figure 1 is a perspective view of a press provided with a punch and die construction of my invention;

Fig.2 is a vertical section through my improved die mechanism before the pressing operation; 1;:

Fig. 3 is a vertical section through the die mechanism after the pressing operation has been completed and before separation of the punch and die; Fig. 4 is a fragmentary perspective view showing corners of a sheet metal article flanged according to my invention; I

Fig. 5 is a perspective view of a sheet metal article similar to'that shown in Fig. $341M! the portions intermediate the corners have been flanged to form a peripheral flange;

Fig. 6 is a plan view taken on line 66 of F i 2 showing the die and associated arts;

ig. 7 is a plan view on line 77 of ig. 2 showing the punchvand associated parts, and showing a portion of flanged; sheet metal disposed on said punch; r v

Fig. 8 is a fragmentary plan view of a portion of sheet metal having a completely formed corner .flange and a beaded edge;

Fig. 9 is a vertical section on line 9-9 of Fig 8; and

ig. is an elevation showing a portion of sheet metal with a corner flange formed therein and trimmed to size. r

Indicated generally by the numeral'l is shown a conventional press of the reciproca-H reciprocating plate 2 by suitable means such forming operation.

as the bolts 7 The die 4 comprises a projecting portion 8 having the angularly dis-. posed sides 9 and 10 which enclose the recess 11. The sides 9 and 10 may be disposed at any desired angle to each other, such as an; acute, right, or obtuse angle, depending on the shape of corner flange desired to be formed in the sheet metal to be shaped. The die shoe'6 is also shown as provided with a pair of sockets 12 to cooperate with guide pins 13 to be described hereinafter.

Yieldingly mounted outwardly of the recess 11 is the blank holder 14, which serves to cooperate with the punch 5 to hold the sheet metal firmly in position during the The blank holder 14 is supported in extended position from the die shoe by bolts 15 engaging in the-shouldered sockets 16 in the die shoe. The blank holder 14 is guided during movement by the guide pins 17, which are spaced from the reciprocatlng plate 2 by springs 18 disposed intermediate the inner ends of the pins 17 and the,

plate 2. Disposed "in the socket 19 and cooperating with the base of said socket and the inner side of the blank holder 14, is shown a relatively heavy spring 20 which is adapted to maintain the blank holder in firm but yieldmg relation to the sheet metal 21 to beformed,

duringthe forming operation. As indicated m F igs. 2 and 3, the outer surface of the blank holder 14 may be suitably shaped to cooperate with the outer surface of the punch 5 to form a beaded edge 22; adjacent the top portion of theflange 23 to be formed in the sheet metal 21. The outer surface of the blank holder 14 is preferably normally in substantially the same plane as the outer surface of the projecting sides 9 and 10 as indicated in Fig. 2. l

The punch 5 is mounted on, and is shown as forming an integral part of, the punch base 24 which is suitably secured to the bolster plate 3 as by bolts 25. Also carried by 5 is angularly formed to extend into the recessll of the die 4 and has the angularly disposed sides 26 and 27 to cooperate closely with the angularly disposed sides 9 and 10 of the die 4. The outer surface of the punch 5 is shaped to conform to the interior surface toibe formed in the sheet metal 21, and in the present case the punch is shown as provided with a raised edge 28, whereby the said punch may cooperate with the blank holder 14,-which is provided with a corresponding depression, whereby a raised beaded edge may be formed in the sheet metal. It will be understood, of course, that the outer surfaces of the punch 5 and blank holder 14 may be shaped in any maner to provide a desired configuration on the sheet metal to be shaped.

Below the bolster plate 3'is shown a pad 29 which is shown as resiliently supported by a plurality of relatively heavy springs 30. Spaced from the angularly disposed sides 26 and 27 of the punch 5 are the guide plates 31 and 32 which are resiliently mounted on the light springs 33 which, in turn, are supported on the pad 29. By means of these guide plates the corner portion of the sheet metal 21 to be formed may be readily disposed in desired position. Adjacent the corner of the punch 5 but spaced therefrom is a drawplate 34 which is supported on the pad 29 by means of the pins 35. As indicated in Fig. 2, the outer surface of the drawplate 34 is disposed normally in substantially the same plane as the outer surface of the punch 5. The drawplate 34 serves to hold or support the outer corner 36 of the sheet metal 21 during the forming operation, whereby a relatively smooth depending flange may be formed in the sheet metal.

In operation, the piece of sheet metal 21 to be formed, preferably of the shape indicated in thedotted line in Fig. may be disposed intermediate the punch 5 and die 4 and in cooperative relation to the guide plates 31 and 32 and drawplate 34 as indicated in Figs. 2 and 7. Relative movement of the punch and die toward each other is then caused to take place in the present instance by lowering the reciprocating plate 2. As a result of the movement of the die 4 toward the punch 5, the blank holder 14 and punch 5 cooperate to hold the sheet metal firmly, and meanwhile the sides 9 and 10 of the die 4 cooperate with the punch 5, to form the depending sides 37 and 38 of the flange 23 in the sheet metal 21. During the formation of the flange the drawplate 34 holds the outer corner 36 of the sheet metal 21, whereby a relatively smooth depending flange 23 is formed. The drawplate 34 cooperates with the outer edge 36 until the flange is substan tially completely formed. The position of the parts when the flan e has been completely formed is shown in ig. 3.

It will be noted that as a result of supporting the sheet metal to be formed by my unproved mechanism, a relatively smooth flange is formed and the excess metal adjacent the corner 36 extends outwardly in the manner indicated in Figs. 8 and 9, wherein are shown the shape of the sheet metal after the completion of the forming operation. It will be understood, of course, that the sheet metal may be shaped with or without the beaded edge 22.

The excess metal at 36 maybe trimmed ofl in a subsequent operation to an even edge as indicated in Fig. 10. In Fig. 4 is shown a piece of sheet metal wherein a plurality of corner flanges have been formed. By a subsequent flanging operation the portions intermediate the corners may be flanged to form an article provided with a completely pe ripheral flange as shown in Fig. 5.

It will thus be seen that I have provided mechanism whereby a relatively smooth depending corner flange may be formed to form polygonal articles of desired size. and number of sides.

Applicants copending application Serial No. 259,665, "filed March 7, 1928, contains claims generic to the construction shown and described herein.

Furthermore, it is to be understood that the particular forms of apparatus shown and described-,and the particular procedure set forth, are presented for purposes of explanation and illustration and that various modifications of said apparatus and procedure can be made without departing from my invention as defined in the appended claims.

What I claim is:

1. In apparatus for forming a depending corner flange insheet nietal, in combination,

a stationary punch sha d to conform to the interior surface to be formed in said sheet metal, a'movable die adapted to cooperate with said punch to form said sheet metal to the desired shape and having a projecting portion to partially enclose a recess, said punch and die being shaped to form a corner flange in said sheet metal, a blank holder yieldingly mounted outwardly of said recessed portion and -cooperable with said punch to form a bead adjacent the top portion of said flange, said blank holder and punch cooperating to hold the body of the sheet metal firmly in non-slipping fashion during the operation of the apparatus, a drawplate yieldingly mounted adjacent, but

means moving said die toward said punch.

2. In apparatus for forming 9. depending corner flange in sheet metal, in combination, a stationary punch shaped to conform to the interior surface to be formed in said sheet metal, a movable die adapted to cooperate with said punch to form said sheet metal. to the desired shape, said die having a projecting portion to partially enclose a recess, said punch and die being shaped to form a corner'flange in said sheet metal, a blank holder yieldingly mounted outwardly of said recessed portion with the outer surface of said blank holder normally in substantially the same plane as the outer surface of said projectingportion, said blank holder and punch cooperating to grip the bodyof the sheet metal firmly to prevent slippage thereof during the operation of the apparatus, a drawplate yieldingly mounted adjacent said punch in alignment with said projecting portion, the outer surface of said drawplate lying normally in substantially the same plane as the outer surface of said punch and spaced from said punch, said drawplate being arranged to hold the corner portion of the sheet metal until said depending flange is substantially completely formed, and means for moving said die toward said punch.

3. In apparatus for forming a depending corner flange in sheet metal, in combination, a punch base, a punch mounted on said base shaped to conform to the interior surface to be formed in said sheet metal, a die shoe, a die carried by said die shoe adapted to cooperate with said punch to form said sheet metal to the desired shape, said die having a projecting portion to partially enclose a recess, said punch and die being shaped to form a corner flange in said sheet metal, a blank holder yieldingly mounted outwardly of said recessed portion with the outer surface of said blank holder normally in substantially the same plane as the outer surface of said projecting portion, said blank holder and punch being arranged togrip the bodyof said sheet metal in non-slipping fashion during the operation of the apparatus, a drawplate yieldingly mounted adjacent, but in spaced relation to, said punch and, in alignment with said projecting portion, the outer surface of said drawplate being disposed normally in substantially the same plane as the outer surface of said punch, said drawplate being arranged to support the corner portion of said sheet metal until said flange is substantially completely formed, guide plates yieldingl mounted in cooperation with said punch base whereby sheet metal may be accurately positioned inin spaced relation-to, said punch and im termediate said punch and die, and means alignment with said projecting portion, said drawplate being arranged to hold the corner portion of said sheet metal until'sai-d flange is substantially completely formed, I and ,for causing relative movement of said punch and die toward, and away from,each other.

4. In metal flanging apparatus for forming a fractional flange on a peripheral portion of .a sheet metal blank, a stationary punch, a movable die cooperable with said punch, a yieldable blank holder arranged to cooperate with said punch to grip the blank being flanged, a draw plate laterally spaced from said punch and bein cooperable with said die to grip the perip eral portion of the blank being flanged with less force than said blank holder, a yieldable pressure pad below said punch, and a plurality of pins supporting said draw plate on said pressure pad.

5. In metal flanging apparatus for forming a fractional corner flange on a peripheral portion of a sheet metal blank, a punch, a die coo erable with said punch, said die and I punch avin rigid projecting portions con-.

forming in s ape to the fractlonal flange to be formed, a spring pressed blank holder associated with said die substantially coplanar with the face of the projecting portion of said die and arranged to cooperate and means for providing relative movements with the pro'ecting portion of said punch to grip the blan being flanged,a spring pressed draw plate associated with said punch substantially coplanar with the face of the projecting portion of said punch and arranged to cooperate with the projecting portion of said die to grip the peripheral portion being flanged with less force than said blank holder,

of said punch and die.

In testimony whereof I aflix my signature.

JAMES A. MCGREGOR. 

